1 /* 2 * Copyright (c) 2009 Pawel Jakub Dawidek <pjd@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Copyright (c) 2012 Spectra Logic Corporation. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/ck.h> 34 #include <sys/epoch.h> 35 #include <sys/kernel.h> 36 #include <sys/kmem.h> 37 #include <sys/lock.h> 38 #include <sys/mutex.h> 39 #include <sys/queue.h> 40 #include <sys/taskq.h> 41 #include <sys/taskqueue.h> 42 #include <sys/zfs_context.h> 43 44 #if defined(__i386__) || defined(__amd64__) || defined(__aarch64__) 45 #include <machine/pcb.h> 46 #endif 47 48 #include <vm/uma.h> 49 50 #if __FreeBSD_version < 1201522 51 #define taskqueue_start_threads_in_proc(tqp, count, pri, proc, name, ...) \ 52 taskqueue_start_threads(tqp, count, pri, name, __VA_ARGS__) 53 #endif 54 55 static uint_t taskq_tsd; 56 static uma_zone_t taskq_zone; 57 58 taskq_t *system_taskq = NULL; 59 taskq_t *system_delay_taskq = NULL; 60 taskq_t *dynamic_taskq = NULL; 61 62 proc_t *system_proc; 63 64 extern int uma_align_cache; 65 66 static MALLOC_DEFINE(M_TASKQ, "taskq", "taskq structures"); 67 68 static CK_LIST_HEAD(tqenthashhead, taskq_ent) *tqenthashtbl; 69 static unsigned long tqenthash; 70 static unsigned long tqenthashlock; 71 static struct sx *tqenthashtbl_lock; 72 73 static taskqid_t tqidnext; 74 75 #define TQIDHASH(tqid) (&tqenthashtbl[(tqid) & tqenthash]) 76 #define TQIDHASHLOCK(tqid) (&tqenthashtbl_lock[((tqid) & tqenthashlock)]) 77 78 #define TIMEOUT_TASK 1 79 #define NORMAL_TASK 2 80 81 static void 82 system_taskq_init(void *arg) 83 { 84 int i; 85 86 tsd_create(&taskq_tsd, NULL); 87 tqenthashtbl = hashinit(mp_ncpus * 8, M_TASKQ, &tqenthash); 88 tqenthashlock = (tqenthash + 1) / 8; 89 if (tqenthashlock > 0) 90 tqenthashlock--; 91 tqenthashtbl_lock = 92 malloc(sizeof (*tqenthashtbl_lock) * (tqenthashlock + 1), 93 M_TASKQ, M_WAITOK | M_ZERO); 94 for (i = 0; i < tqenthashlock + 1; i++) 95 sx_init_flags(&tqenthashtbl_lock[i], "tqenthash", SX_DUPOK); 96 taskq_zone = uma_zcreate("taskq_zone", sizeof (taskq_ent_t), 97 NULL, NULL, NULL, NULL, 98 UMA_ALIGN_CACHE, 0); 99 system_taskq = taskq_create("system_taskq", mp_ncpus, minclsyspri, 100 0, 0, 0); 101 system_delay_taskq = taskq_create("system_delay_taskq", mp_ncpus, 102 minclsyspri, 0, 0, 0); 103 } 104 SYSINIT(system_taskq_init, SI_SUB_CONFIGURE, SI_ORDER_ANY, system_taskq_init, 105 NULL); 106 107 static void 108 system_taskq_fini(void *arg) 109 { 110 int i; 111 112 taskq_destroy(system_delay_taskq); 113 taskq_destroy(system_taskq); 114 uma_zdestroy(taskq_zone); 115 tsd_destroy(&taskq_tsd); 116 for (i = 0; i < tqenthashlock + 1; i++) 117 sx_destroy(&tqenthashtbl_lock[i]); 118 for (i = 0; i < tqenthash + 1; i++) 119 VERIFY(CK_LIST_EMPTY(&tqenthashtbl[i])); 120 free(tqenthashtbl_lock, M_TASKQ); 121 free(tqenthashtbl, M_TASKQ); 122 } 123 SYSUNINIT(system_taskq_fini, SI_SUB_CONFIGURE, SI_ORDER_ANY, system_taskq_fini, 124 NULL); 125 126 #ifdef __LP64__ 127 static taskqid_t 128 __taskq_genid(void) 129 { 130 taskqid_t tqid; 131 132 /* 133 * Assume a 64-bit counter will not wrap in practice. 134 */ 135 tqid = atomic_add_64_nv(&tqidnext, 1); 136 VERIFY(tqid); 137 return (tqid); 138 } 139 #else 140 static taskqid_t 141 __taskq_genid(void) 142 { 143 taskqid_t tqid; 144 145 for (;;) { 146 tqid = atomic_add_32_nv(&tqidnext, 1); 147 if (__predict_true(tqid != 0)) 148 break; 149 } 150 VERIFY(tqid); 151 return (tqid); 152 } 153 #endif 154 155 static taskq_ent_t * 156 taskq_lookup(taskqid_t tqid) 157 { 158 taskq_ent_t *ent = NULL; 159 160 sx_xlock(TQIDHASHLOCK(tqid)); 161 CK_LIST_FOREACH(ent, TQIDHASH(tqid), tqent_hash) { 162 if (ent->tqent_id == tqid) 163 break; 164 } 165 if (ent != NULL) 166 refcount_acquire(&ent->tqent_rc); 167 sx_xunlock(TQIDHASHLOCK(tqid)); 168 return (ent); 169 } 170 171 static taskqid_t 172 taskq_insert(taskq_ent_t *ent) 173 { 174 taskqid_t tqid; 175 176 tqid = __taskq_genid(); 177 ent->tqent_id = tqid; 178 ent->tqent_registered = B_TRUE; 179 sx_xlock(TQIDHASHLOCK(tqid)); 180 CK_LIST_INSERT_HEAD(TQIDHASH(tqid), ent, tqent_hash); 181 sx_xunlock(TQIDHASHLOCK(tqid)); 182 return (tqid); 183 } 184 185 static void 186 taskq_remove(taskq_ent_t *ent) 187 { 188 taskqid_t tqid = ent->tqent_id; 189 190 if (!ent->tqent_registered) 191 return; 192 193 sx_xlock(TQIDHASHLOCK(tqid)); 194 CK_LIST_REMOVE(ent, tqent_hash); 195 sx_xunlock(TQIDHASHLOCK(tqid)); 196 ent->tqent_registered = B_FALSE; 197 } 198 199 static void 200 taskq_tsd_set(void *context) 201 { 202 taskq_t *tq = context; 203 204 #if defined(__amd64__) || defined(__aarch64__) 205 if (context != NULL && tsd_get(taskq_tsd) == NULL) 206 fpu_kern_thread(FPU_KERN_NORMAL); 207 #endif 208 tsd_set(taskq_tsd, tq); 209 } 210 211 static taskq_t * 212 taskq_create_impl(const char *name, int nthreads, pri_t pri, 213 proc_t *proc __maybe_unused, uint_t flags) 214 { 215 taskq_t *tq; 216 217 if ((flags & TASKQ_THREADS_CPU_PCT) != 0) 218 nthreads = MAX((mp_ncpus * nthreads) / 100, 1); 219 220 tq = kmem_alloc(sizeof (*tq), KM_SLEEP); 221 tq->tq_queue = taskqueue_create(name, M_WAITOK, 222 taskqueue_thread_enqueue, &tq->tq_queue); 223 taskqueue_set_callback(tq->tq_queue, TASKQUEUE_CALLBACK_TYPE_INIT, 224 taskq_tsd_set, tq); 225 taskqueue_set_callback(tq->tq_queue, TASKQUEUE_CALLBACK_TYPE_SHUTDOWN, 226 taskq_tsd_set, NULL); 227 (void) taskqueue_start_threads_in_proc(&tq->tq_queue, nthreads, pri, 228 proc, "%s", name); 229 230 return ((taskq_t *)tq); 231 } 232 233 taskq_t * 234 taskq_create(const char *name, int nthreads, pri_t pri, int minalloc __unused, 235 int maxalloc __unused, uint_t flags) 236 { 237 return (taskq_create_impl(name, nthreads, pri, system_proc, flags)); 238 } 239 240 taskq_t * 241 taskq_create_proc(const char *name, int nthreads, pri_t pri, 242 int minalloc __unused, int maxalloc __unused, proc_t *proc, uint_t flags) 243 { 244 return (taskq_create_impl(name, nthreads, pri, proc, flags)); 245 } 246 247 void 248 taskq_destroy(taskq_t *tq) 249 { 250 251 taskqueue_free(tq->tq_queue); 252 kmem_free(tq, sizeof (*tq)); 253 } 254 255 int 256 taskq_member(taskq_t *tq, kthread_t *thread) 257 { 258 259 return (taskqueue_member(tq->tq_queue, thread)); 260 } 261 262 taskq_t * 263 taskq_of_curthread(void) 264 { 265 return (tsd_get(taskq_tsd)); 266 } 267 268 static void 269 taskq_free(taskq_ent_t *task) 270 { 271 taskq_remove(task); 272 if (refcount_release(&task->tqent_rc)) 273 uma_zfree(taskq_zone, task); 274 } 275 276 int 277 taskq_cancel_id(taskq_t *tq, taskqid_t tid) 278 { 279 uint32_t pend; 280 int rc; 281 taskq_ent_t *ent; 282 283 if (tid == 0) 284 return (0); 285 286 if ((ent = taskq_lookup(tid)) == NULL) 287 return (0); 288 289 ent->tqent_cancelled = B_TRUE; 290 if (ent->tqent_type == TIMEOUT_TASK) { 291 rc = taskqueue_cancel_timeout(tq->tq_queue, 292 &ent->tqent_timeout_task, &pend); 293 } else 294 rc = taskqueue_cancel(tq->tq_queue, &ent->tqent_task, &pend); 295 if (rc == EBUSY) { 296 taskqueue_drain(tq->tq_queue, &ent->tqent_task); 297 } else if (pend) { 298 /* 299 * Tasks normally free themselves when run, but here the task 300 * was cancelled so it did not free itself. 301 */ 302 taskq_free(ent); 303 } 304 /* Free the extra reference we added with taskq_lookup. */ 305 taskq_free(ent); 306 return (rc); 307 } 308 309 static void 310 taskq_run(void *arg, int pending __unused) 311 { 312 taskq_ent_t *task = arg; 313 314 if (!task->tqent_cancelled) 315 task->tqent_func(task->tqent_arg); 316 taskq_free(task); 317 } 318 319 taskqid_t 320 taskq_dispatch_delay(taskq_t *tq, task_func_t func, void *arg, 321 uint_t flags, clock_t expire_time) 322 { 323 taskq_ent_t *task; 324 taskqid_t tqid; 325 clock_t timo; 326 int mflag; 327 328 timo = expire_time - ddi_get_lbolt(); 329 if (timo <= 0) 330 return (taskq_dispatch(tq, func, arg, flags)); 331 332 if ((flags & (TQ_SLEEP | TQ_NOQUEUE)) == TQ_SLEEP) 333 mflag = M_WAITOK; 334 else 335 mflag = M_NOWAIT; 336 337 task = uma_zalloc(taskq_zone, mflag); 338 if (task == NULL) 339 return (0); 340 task->tqent_func = func; 341 task->tqent_arg = arg; 342 task->tqent_type = TIMEOUT_TASK; 343 task->tqent_cancelled = B_FALSE; 344 refcount_init(&task->tqent_rc, 1); 345 tqid = taskq_insert(task); 346 TIMEOUT_TASK_INIT(tq->tq_queue, &task->tqent_timeout_task, 0, 347 taskq_run, task); 348 349 taskqueue_enqueue_timeout(tq->tq_queue, &task->tqent_timeout_task, 350 timo); 351 return (tqid); 352 } 353 354 taskqid_t 355 taskq_dispatch(taskq_t *tq, task_func_t func, void *arg, uint_t flags) 356 { 357 taskq_ent_t *task; 358 int mflag, prio; 359 taskqid_t tqid; 360 361 if ((flags & (TQ_SLEEP | TQ_NOQUEUE)) == TQ_SLEEP) 362 mflag = M_WAITOK; 363 else 364 mflag = M_NOWAIT; 365 /* 366 * If TQ_FRONT is given, we want higher priority for this task, so it 367 * can go at the front of the queue. 368 */ 369 prio = !!(flags & TQ_FRONT); 370 371 task = uma_zalloc(taskq_zone, mflag); 372 if (task == NULL) 373 return (0); 374 refcount_init(&task->tqent_rc, 1); 375 task->tqent_func = func; 376 task->tqent_arg = arg; 377 task->tqent_cancelled = B_FALSE; 378 task->tqent_type = NORMAL_TASK; 379 tqid = taskq_insert(task); 380 TASK_INIT(&task->tqent_task, prio, taskq_run, task); 381 taskqueue_enqueue(tq->tq_queue, &task->tqent_task); 382 return (tqid); 383 } 384 385 static void 386 taskq_run_ent(void *arg, int pending __unused) 387 { 388 taskq_ent_t *task = arg; 389 390 task->tqent_func(task->tqent_arg); 391 } 392 393 void 394 taskq_dispatch_ent(taskq_t *tq, task_func_t func, void *arg, uint32_t flags, 395 taskq_ent_t *task) 396 { 397 int prio; 398 399 /* 400 * If TQ_FRONT is given, we want higher priority for this task, so it 401 * can go at the front of the queue. 402 */ 403 prio = !!(flags & TQ_FRONT); 404 task->tqent_cancelled = B_FALSE; 405 task->tqent_registered = B_FALSE; 406 task->tqent_id = 0; 407 task->tqent_func = func; 408 task->tqent_arg = arg; 409 410 TASK_INIT(&task->tqent_task, prio, taskq_run_ent, task); 411 taskqueue_enqueue(tq->tq_queue, &task->tqent_task); 412 } 413 414 void 415 taskq_wait(taskq_t *tq) 416 { 417 taskqueue_quiesce(tq->tq_queue); 418 } 419 420 void 421 taskq_wait_id(taskq_t *tq, taskqid_t tid) 422 { 423 taskq_ent_t *ent; 424 425 if (tid == 0) 426 return; 427 if ((ent = taskq_lookup(tid)) == NULL) 428 return; 429 430 taskqueue_drain(tq->tq_queue, &ent->tqent_task); 431 taskq_free(ent); 432 } 433 434 void 435 taskq_wait_outstanding(taskq_t *tq, taskqid_t id __unused) 436 { 437 taskqueue_drain_all(tq->tq_queue); 438 } 439 440 int 441 taskq_empty_ent(taskq_ent_t *t) 442 { 443 return (t->tqent_task.ta_pending == 0); 444 } 445